This invention pertains to filtering devices, and in particular a smoke and pollutant filtering device comprising a series of contiguous layers of filtering material.
On Nov. 22, 1980 the MGM Grand Hotel in Las Vegas, Nevada experienced a fire in its lower casino level which burned out of control for a short period of time. Toxic gases generated by the fire were drawn into the hotel ventilation system and spread throughout the sleeping areas of the hotel, killing many persons who died of smoke inhalation without being burned or experiencing any of the heat of the fire. Most, if not all, of those killed by smoke inhalation could have survived had they had access to a mask for filtering the deadly components from the smoke and gases which were spread throughout the hotel, giving the patrons sufficient time to find an exit to fresh air.
Many types of smoke and gas masks are well known and have been used for decades. Typical such masks include a pliable face portion with integral goggles to permit sight, and a canister of filtering material, such as activated charcoal, either forming a part of the mask or separately connected to the mask in order to permit air purification. Such masks are, however, bulky and cumbersome, and typically quite costly to manufacture. As a result, life saving masks are rarely, if ever, found in hotels and other public places where use in an emergency situation would undoubtedly save many lives.